Art of manufacturing collapsible cores.



Patented Nov. 12, 1918.

2 SHEETS-SHEEI l.

. T MIDGLEY Sn ART OF MANUFACTURING COLLAPSIBLE CORES.

. I APPLICATION FILED MAR. 7.19- 1,284,414.

T. MIDGLEY, SR. ART OF MANUFACTURING COLLAPSIBLE CORES.

I APPLICATION FILED MAR. 7. 19I7. 1,284,414.

2 SHEETSSHEEI 2.

I/OMAS NIDGLEY, SR.

Patented Nov. 12, 1918.

THOMAS IMI'DGJLEY, SB., OF COLUMBUS, OHIO.

ART OF MANUFACTURING COLLAPSIBLE GORES.

Specification of Letters Patent.

Patented NOV. 12, 1918.

Application filed March 7, 1917. Serial No. 153,145.

To all whom it may concern:

Be it known that I, THOMAS MIDGLEY, Sr., a citizen of the United States, residing at Columbus, in the county of Franklin and State of Ohio, have invented certain new and useful Improvements in the Art of Manufacturing Collapsible Cores, of whichv the following is a specification.

This invention relates to the art of manufacturing collapsible cores and which cores are designed for use in the manufacture of pneumatic tire casings, preferably inextensible edged casings.

The main ob 'ect of this invention resides in the method of constructing these collapsible cores wherein the face plates for the ends of the abutting sections forming the annulus are securely fastened to the core sections and bonded in such manner as to make a perfect joint both between the face plates and the core ends and between the face plates themselves. This method is primarily for use where the facings for the ends of the core sections are placed in the imprint and attached to the ends by casting the sections thereon. By constructing the cores in this manner, considerable difficulty has arisen in making the bond between the face plates and the core sections so that a perfect joint is formed, which will not require plugging after the core itself has been finished. My improved method for overcoming this consists in enlarging the imprint at the point in the mold where these end plates are placed prior to the casting'operation, so that a surplus of metal is formed at this point. Inasmuch as practically all imperfections in casting occur within the surface, such as blow holes or sand holes, these imperfections can be removed during the finishing process of the core and thus a perfeet joint between the face plates and the core sections, is formed.

A further object of my invention resides in a method for preventing the admission of any molten metal between the separable members of the abutting face plates during the casting operation. When this metal is in a highly heated state, it readily finds its way through all openings or crevices and to thisend, I provide a plurality of plates sufficient for each set, which are larger than the finished core and arrange theseplates in sets and after arranging these plates in sets,

I seal the edges of them together to complates of each pletely guard against the admission of the molten metal between them and after the casting operation, remove this surplus metal and face plates which latter forms a part of the finishing operation.

Still a further object of my invention resides in a method whereby the means for holding the various core sections in their assembled relation, is cast into position during the casting operation, thus eliminating all machine work as regards this feature.

In the accompanying sheets of drawings, I have shown a completed core constructed in accordance with my improved methods of manufacture and also have attempted to show the relative positions of certain of the parts within the mold imprint prior to the casting operation. In these several views, similar characters of reference designate corresponding parts, and

Figure 1 represents a completed'eore partially shown in side elevation and partially shown in section,

Fig. 2 is an end view of one of the core sections after the core has been completed. as represented approximately on line 2-2 of Fig. 1,

Fig. 3 is a top view showing the plates forming one set in their proper position {within the lower half or drag of the mold Fig. 1 is a cross section taken through line 5-5 of Fig. Land,

Fig. 5 shows the relative positions of the face plates and drag and the shape to which the imprint is formed as represented approximately on line 6-6 of Fig. 3.

The present core when finished, is formed of a plurality of sections '1 and 2 sufiicient in number to form an annulus, over which the tire may be built. The abutting ends of the sections 1 and 2, as shown, are of general Z-shape, the leg portions 'belng designated generally by the reference numerals 3 and 4 and the intermediate portion by the reference numeral 5. These abutting ends are preferably faced with face plates such as shown at 6. I have shown four plates 6, as comprising each set, two plates of each set being riveted or spot welded together and the outside pair being stamped out as is shown at 7, so that these face plates may be rigidly attached to the core segments during the process of casting, by placing the assembled plates in their proper relation in the mold imprint. These plates 6 are provided with concaved portions 8, so that a tongue and groove structure is provided for the ends of the abutting sections to prevent sidewise or lateral play. Further, the intermediate portions 5 of these plates are preferably shaped to present an offset 9, the oflset, as shown, being in a direction toward the outer periphery of the annulus as a whole. This latter construction is provided to relieve circumferential strain when pressure is applied to the sides of the tire casing before and during the time it is cured, when this pressure is applied directly to the sides, the natural tendency of this core is to expand and to do this, there must be separation between the abutting ends of the core section. To overcome this, I have provided the offset portion 9 to relieve the cir-- cumferential strain and I prevent direct separation between the core sections by means of thebolt and nut structure to be presently described.

In forming the various division plates or sets, I form each set of a plurality of plates which are larger than the finished core, but which are smaller than the corresponding portion of the imprint and arrange these plates in sets. After sealing the edges of these sets to guard against the admission of molten metal between them, I place them in the imprint, and because of the enlargement, the metal is permitted to flow from one section to another and in so doing, covers the sealed edges to form ahead at this point The core, just after casting is a complete one piece annulus and remains such until the surplus metal allowed for finishing purposes and the surplus metal constituting the head around the face plates, is removed. On

Sheet 2, the various plates 6 are shown as previously described, the outside plates for each set of four being stamped out as shown at 7, to form the means of connection between the cast core sections and the plates themselves. The two inner plates 6' are not attached to each other, but each of these inner platesis rigidly attached to one of the outer plates. Both the inner and outer plates are slightly larger than it is intended the finished core "shall be, which has been represented by the dotted finish line 10. The

lower half of the mold or the drag portion is represented by the reference numeral 11 and the pattern for the core forms the properly shaped imprint 12 therein. At the point where the face plates occur, this imprint is enlarged as shown at 13, so that. a bead of cast metal will be formed at a point where each of these face plates occur. Also, this imprint is slightly tapered away, as shown at 14, to permit the free flow of metal from one section to another during the casting operation. By means of these enlargements,

the outer plates.

meagre? 7 any sand which is collected by the metal during the time it is running through-the mold, will collect therein to prevent sand holes in the finished article. Also, there being a considerable surplus of metal at the point where the face plates occur, the metal at the finish level of the core, is not chilled readily when being poured in the mold and consequently, a great/er time is allowed for it to shape itself or set in connection with the face plates. Where this metal is rapidly chilled, it does not flow as freely as it should and in this way oftentimes prevents the formation of a perfect bond. By my improved method as outlined, this is overcome.

As has been related, each set of plates constitutes four individual plates, as shown, and the inner plates 6 are slightly smaller in size than the outer plates. After the set has been assembled, the space 15 formed between the two outer plates is filled with some sealing material such as core sand. After this, a channel-shaped structure 16 is clamped into position, which additionally seals the edges of each set to prevent the admission- .which latter isprovided with a tongue 20 of a size to tightly fit the space 15 formed at the rear end of each set due to the inner plates being of a slightly smaller size than The tongue of this supporting element 19 enters this space and, therefore, forms the means of supporting the rear end of the face plates in the imprint. By this arrangement. it will be apparent that admission of molten metal between the plate sections to cause their fusing together is impossible and also by means of the enlargements 13 and 14, sufiicient metal is cast around this portion of the core to form a perfect joint.

In order to eliminate all machine work as regards the means for holding the core sections in their assembled relation, each of the plates constituting the division set, is

into position as is shown, its head 25 engag 1:

ing the thimble 23 to wedge itagainst one of the outer plates and the threads on the shank of the bolt 24 engaging the threads within the nut to wedge it into contact with the opposite outside plate. The imprint is also suitably formed to receive the head 25 of the bolt as is shown on Sheet 2 and in this manner a third point of support for the assembled division plates within the imprint, is formed. The endof'the nut 22 is filled with core sand, or some other sealing medium, as shown at 26 and thus, when the core is cast the metal formin the various sections flows about the thimile and the nut so that these two are bonded or securely held in position after the metal cools. Further, these members are in proper alinement with each other to properly hold the core in its assembled relation. After casting, the temporary bolt 24 can, of course, be removed and a higher grade bolt inserted. Inasmuch as the thimble and nut are securely drawn toward each other when the plates are placed in the mold, the joint formed between the separable portions of the division plates can also be made perfect.

From the foregoing description, it will appear that I have provided a method wherein a perfect union between the faceplates and the east sections may be had. This is effected by enlarging the imprint as shown at 13 and 14 to provide a surplus of mate at this point during the casting operation. The molten metal is prevented from entering the spaces between the face plates because of their sealed edges as related. Finally, the core sections are provided with means for holding them in their assembled relation because of the thimble 23, nut 22 and bolt 24. After the core has been cast, it is machined to a finish along approximately the line shown at 10, which finishing operation removes the surplus plates 6 and also the surplus cast metal. The sealing channel 16 comes off in this finishing operation and after this, removal of the bolts 24 permits the core sections to be separated.

What I claim is 1. The method of constructing collapsible cores wherein the facings for the ends of the core sections are placed in the imprint and attached to said ends by casting the sections thereonto which consists in enlarging the imprint 'at the place. where said plates occur, casting, and then finishing by removing the surplus cast metal and plates.

2. The method of constructing collapsible cores wherein the facings for the ends of the core sections are placed in the imprint and attached to said ends by casting the sections thereonto which consists in selecting-plates which are larger than the finished core, arranging them in sets and placlng 1 them in the imprint, enlarging the imprint at the place where said plates occur s9 that a bead will be formed over the edges of the plates, casting, and then finishing by removing the surplus cast metal and plates.

3. The method of constructing collapsible cores wherein the facings for the ends of the core sections are placed in the imprint and attached to said ends by casting the sections thereonto which consists in selecting plates larger than the finished core and arranging said plates in sets, sealing the edges of said lates to reclude entrance of molten metal etween t em, supporting said sets in the imprint so that the molten metal flows from one section to another and covers the sealed edges of said sets, casting, and then removing the surplus cast metal and plates.

,4. The method of constructing division plate sets for collapsible cores which consists in forming a plurality of plates for each set to a slze larger than the finished core but smaller than the corresponding portions of the im rint, arranging said plates in sets, and sea ing the edges of' said sets together to guard against the admission of molten metal between them.

5. The method of constructing division plate sets for collapsible cores which consists in form a plurality of plates for each set to a size larger than the finished core but smaller than the corresponding portions .of the imprint, the inner abutting plates being smaller than the outer plates, filling. the space thus formed between the outer plates with a sealing medium, and

then clamping a metal strip around the edge of each set of plates to additionally guard against the admission of molten metal between them.

6. The method of constructing collapsible cores which consists in assembling a lurality of end' plates arranged in a set be ore casting to form face plate for abutting sections, placing such set in the imprint and supporting a bolt and nut on opposite sides of said setso that the retaining means for holding the abutting sections together are fastened into proper alining positlon during the casting operation. V

7. The method of constructing collapsible cores which consists in assembling a.plu-- rality of end plates arranged in a set before casting to .form face plates for the abutting sections, supporting a nut'on one side and a thimble on the other side of said set in alinement with each other, placing said set, nut and thimble in an imprint, and then casting.

8. The method of constructing collapsible cores which consists in assembling a plurality of end plates arranged in a set before casting to form face plates for the abutting sections, supporting a nut on one side and a thimble on the other side of said set in alinement witheach other, by means of a 10 into one core section and supporting means which form an alining opening with said nut on the other side of said set so that the other core section will have the alim'ng hole formed therein, and then casting.

In testimony whereof I aflix my signa- 15 ture in presence of two witnesses. 7

THOMAS MIDGLEY, SR. Witnesses:

WALTER E. L. BocK, A. L. PHELPS. 

